Brotherhood
I'm not sure but you might be right
Platonic soul mates
It's either I need to expand my vocabulary or the english language is limited. Also great idea to just put them together. I feel stupid not thinking to just combine it.
It's uncommon English vocabulary, and a more modern phrase, but other people use it too. Don't worry though your English vocabulary is still scholarly level and not just native fluency level if you understand these hard words.
In the mid-west, we call that right there "best friends/buddies"
I feel like best friends are different. The friendship lasts however long, and isn't a committed relationship with each other forever.
It's hard to think that they're just best friends or buddies because of how much they are a ride or die for each other.
Bromance. I'll go with bromance.
Y'all I know that they are all just friends but I can't help but see it as more. Not the lovers kind of love but something closer to platonic. Fei and Tougo feel closer to soulmates to me though. This is hard to put into words.